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Second shot at Homeyer TPoint

Went down and adjusted the polar alignment again as per last night’s TPoint model.

Started another 300 point run. Problem: about 30 points in, the system stopped with the message “Mount hit something or is unbalanced”. Drove down and checked – nothing was hitting the mount. Two possibilities:

1) The slight imbalance in the DEC axis is causing a problem.

2) It got cold – maybe the thing where the mount switches speed based on the temperature. Maybe I need to set the temperature limit a bit higher.

Restarted the big run. Did 311 points, with a raw measure of 72.7 arcsec.

Raw results for 311 points

Supermodel gives 6.1 arcseconds:

Supermodel results

Polar alignment now says: off by 67.4 arcseconds in Az (good enough), 75.0 arcseconds in Alt (excellent)

Re-run VCurves, since now I think I need more flux for the Canon. This avoids irregular stars, capturing seeing issues. Looks like 1 second exposures on a Mag 6 star gives 600K flux, reasonably consistent exposures in the log. Run 4 curves, 3 exposures per point, 50 steps per point. Best HFD is around 9. Sweet spot looks like it is 350 steps? Good Near HFD around 15.

Sample VCurve for Canon, Mag 6 star

OK, now that I have the big Supermodel, I tried several 2 minute and 5 minute exposures without guiding – using the ProTrack capability. PEC is running.

Some of the 2 minute ones work fine, but some show distinct elongation in the RA direction. 5 minutes always seem to show the elongation. Don’t see why it would sometimes be bad.

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